Display device having selectively illuminated indicia plates



MaY 7, 1968 R, R. CHRISTY 3,382,495

DISPLAY DEVLCE HAVING SELECTIVELY ILLUMINATED lNDlClA PLATES Filed June 14, 1965 @Sheets-sneer 1 43 an an@ @QDQDGD @DoD/@GD @D /3-2 i" 7Bn Banana l: n: 1 Baumann Zo wwf (E) GD (H) (ID GD GD (D/ @D QD (1D (1D QD sz 0 3o I /3 f2 u '45 l 4-4- /za @-1,50

4o /a a is 44 M m /8 J l s \za "h6 fz s l INVENTOR ROBERT/ (HP/sry BY T/V/ '7M R. R. CHRISTY May 7, 1968 DISPLAY DEVlCE-HAVING SELECTIVELY ILLUMINATED INDICIA PLATES l5 Sheets-Sheet Filed June 14, 1965 /3 JZ 36' J4- /L l/ /m INVENTOR. Pose-Rf CHR/sry A GENT May 7, 1968 R. R. CHRISTY 3,382,495

DISPLAY DEVICE HAVING SELECTIVELY ILLUMINATED NDICIA PLATES Filed June 14, 1965 5 Sheets-Sheet 5 INVENTOR @05E/er CHR/sry A GENT United States Patent C) 3,382,495 DISPLAY DEVICE HAVING SELECTIVELY ILLUMINATED INDICIA PLATES Robert R. Christy, San Marcos, Calif., assigner to Non- Linear Systems, Inc., San Diego, Calif., a corporation of California Filed `lune 14, 1965, Ser. No. 463,728 8 Claims. (Cl. 340-378) ABSTRACT OF THE DISCLOSURE This invention relates to a readout of the type employed in instrument displays wherein visible and changeable characters are to be observed, and is concerned with electrical instruments wherein digital readouts are operated so as to display numerals and other characters or symbols representing values that require observation.

Readouts of the type under consideration are common but they are characteristically large in comparison with the character or symbol height, and are characteristically thick or of substantial depth. The feature which usually requires this ordinary height and thickness is that transparent plates are stacked together and independently edge lighted in order to display a character engraved in any one of the said plates respectively. Essentially, this general arrangement is involved in the present invention, however, improvements are incorporated in the components whereby the disagreeable features prevailing in the prior art structures are eliminated.

A general object of this invention is to provide a cornpact modular unit having improved characteristics, so that it is reasonably simple to manufacture, so that it is easily maintained, and so that visibility and overall effectiveness is increased.

It is an object of this invention to provide such a unit that has high contrast and which greatly increases readability and thereby minimizes eye fatigue, such a unit that induces light to be reflected outwardly with minimized incident light reflections, and such a unit wherein the minimized depth thereof increases the permissible angle of view.

An object of the invention is to provide transparent plates with characters or symbols thereon and which are independently illuminated with minimal effect upon each other. Each transparent plate is individually masked for edge lighting from one predetermined light source and is engraved in such a Way that light is induced to be reilected upon said engraving for ease of observation. As a result, the transparent plates are of reduced and minimal thickness whereby a stack of plates is of much less thickness than in the ordinary prior art structures.

It is an object of this invention to provide a modular -readout unit which in itself is a complete and operative device capable of being plugged into a circuit board for mounting and electrical activation.

It is another object of this invention to provide a readout unit which is made up of easily replaceable components that cooperatively combine for most eflicient operation. The combination is such that any replacement or correction can be accomplished with a minimum of effort, whether it be a replacement necessitated by changed 4requirements or by damaged malfunctioning parts.

It is still another object of the invention to provide a plurality of electrically operable lamps capable of being advantageously installed as a unit, each to individually illuminate a single predetermined transparent plate. Specically, an object is to provide circuit board lamp cornponents which comprise a plurality of lamps controlled by individual circuits and such a component which in rice itself is mounted upon and electrically coupled to a circuit board cooperatively arranged so as to support a multiplicity of adjacent modular units.

The present invention is not only unique in the general objectives thus far referred to, 4but it is also practical and unique in other ways which lend utility and patentability to the invention. These various practibilities will be described in detail and result in a highly ellicient readout characterized mainly by its very brilliant characters or symbols which are easily observed and/or recorded by photographs and the like.

The various objects and features of this invention will be fully understood from the following detailed description of the typical preferred form and application thereof, throughout which description reference is made to the accompanying drawings, in which:

FIG. 1 is a front elevation showing two modular units installed according to the present invention. FIG. 2 is a perspective view of one of the modular readout units shown in FIG. l. FIG. 3 is a sectional view taken as indicated by line 3-3 on FIG. 1. FIG. 4 is an enlarged fragmentary section showing the characteristic feature of the symbols that are made visible. FIG. 5 is an exploded view illustrating the components which comprise the present invention. FIG. 6 is an enlarged sectional view taken as indicated by line 6 6 on FIG. 2. FIGS. 7 and 8 are perspective views of the front and back sides of the mask which characterize the invention. FIG. 9 is a composite view of two illuminated plates and shows one numeral which is visible though it underlies another numeral. FIGS. l0, l1, l2, and 13 are views taken as indicated by lines 10-10, Ill-l1, 12-12, and 13-13 on FIG. 5.

There are many digital or character display devices wherein windows are provided with a stack of transparent plates that are engraved and individually illuminated. These devices are normally characterized by being substantially thick and by stray light which makes visible the characters or Symbols other than those which are desired to be seen. Furthermore, the nature of the ordinary stack of transparent plates makes the edges thereof possible to be seen, when viewed perspectively, especially when illumination of any one of said plates takes place. Also, to View an ordinary readout at any substantial perspective viewpoint results in noticeable displacement of characters, all to the end that the ordinary units are in reality far from satisfactory.

In accordance with the present invention there is a mounting circuit board B adapted to carry and electrically supply a multiplicity of readout units R, each of which is identtical to the other for the purposes of the invention. It is to be understood that the only essential difference between the adjacent units R will be in the particular character and/ or symbol engravings imposed in the plates thereof. As shown adequately in FIG. 2 of the dnawings, the unit R is an erect rectangular solid, from outward appearances, having sides 10, a front 11, a back I2, and top and bottom ends 13, each of which is llat as shown. The unit R is mounted to the mounting circuit board B by means of rearwardly projecting connectors associated with the lamp components later described, and it has a window W in the front 11. FIG. 5 illustrates those components which :are contained within the housing H and which includes a readout stack S, a lamp block L, and a lamp board LB, all of which are carried in working position by and within the housing H.

The mounting circuit board B is provided for support of the modular readout units R and involves a multiplicity of unit positions, two of which are shown occupied by readout units R. The circuit board B is preferred as the means of support and comprises an insulating board 15 with suitable circuitry imprinted thereon `as circumstances require (at the back side and not shown). At the front face of the `board `15 there is ay pair of upper and lower guide strips 16 and 17 disposed horizontally and with opposed parallel faces 18 to slideable receive the upper and lower ends of the -readout units R. Each face 18 hasa key 19 positioned to centrally engage the readout unit which is positioned `thereby. Further, the board 15 is provided with atleast one receptacle 20 or the like, preferably a receptacle 20 ladjacent both the top and bottom strips and disposed parallel with the strips as shown. In the case illustrated, each receptacle has seven circuit connectors, frictionally engageable connectors being employed.

The housing H is provided to enease the components S,L, and LB, and is a tubular part into` which the said components are inserted. As shown, the housing H is vertically disposed and is open at both its top and bottom ends, being composed of the sides 10, front 11, and back 12. The sides and back 12 are imperforate for all practical purposes, the front 11 being provided with a large centrally located window .W. In practice, the interior of the housing H is finished with a dull, black surf-ace for purposes of light absorption.

The readout stack S is an assembly of cooperatively related character frames F each of which comprises a plate 20 carried within a mask 25, said frames F being associated with each other so as to be effectively independent in operation. The plate 20 is of transparent material, preferably of Lucite or the like, and of .030 in. thickness when proportioned as shown. The plate 20 is' a rectangular solid with straight edges and is adapted to p slide within the housing sides 10, and with straight top and bottom ends 21 and 22 adapted to receive and transmit light. The mask 25 is of thin material having a dull black surface at one side 26 and a `specular nish at the other side 27. The side 26 is lat the front or visible side of the mask while the side 27 is in the inside, thereof which faces backward toward the plate 20. In practice the mask is made of aluminum foil of .0055 in. thickness and having a specular nish atside 27 which optically enhances the illumination of the characters later described. As shown, the mask has a window 28 corresponding in size, shape and position with the window W, said windows being rectangular with generously rounded corners.

In accordance with the invention, the masks 25 are descriminately formed so as to selectively admit light at the end or ends of the readout unit R. In practice. eleven characters is suflicient when numerals are involved and the masks 25 are formed and related to each other in order to admit light to but one (or a selected number of) plates 20 at one time. To this end, each mask 25 has top and bottom rails 29, each rail being channel-shaped so as to embrace the opposite edge portions of the plate 20 which slide therein. Thus, the plates 20 are adequately and surely spaced so as not to bear one upon the other, thereby avoiding defacing as by reason of scratching.

The discriminating feature of the masks 25 which distinguishes them from one another, is the provision in each mask 25 of an aperture 31 especially placed to receive a beam of light directed toward the rails 29 of the masks 25. To this end there are as many as six apertures 31 at each end of the readout stack R, therebeing three separately formed masks 25 in order to accomplish this end. That is, there is one mask 25a with an aperture 31 to the left position, there is one mask 25b with an aperture 31 at a centered position, and there is one mask 25e with an aperture 31 to the right position, all as illustrated specifically in FIGS. 10 and 12. Further, in FIGS. 10 and l2 is shown the two opposite top and bottom ends of the readout unit wherein the masks 25 are arranged alternately end for end and the apertures of very other mask are staggered successively from one side to the center and then to the other side positions. This sequence of alternate end for end positioning and transverse staggering, adequately `spaces the apertures 31 for the reception of independent light beams, as will be described. It will be apparent that the plates 20 are individually lighted by beams of light admitted thereto through the apertures 31.

In accordance with the invention, the character `and/ or symbol engravings are unique, involving both the shape or configuration thereof and the placement thereof relative to` each other. A feature is that each character is a composite comprised of a multiplicity of markings or dots that are in the form of light gathering depressions 32 entering the back face of the plate 20.

The depressions 32 are conically shaped substantially as shown about .020 in. in diameter, and they are spaced about .030 in. on centers. It is preferred that the depressions 32 be round, in which case they are readily engraved by use of a revolving tool, or they can be pressed, the degree of finish within said depressions 32 being cornparable to a rather tine ground-glass-nish and which is visibly illuminated when Hooded with light. As pointed out above, placement of the depressions 32 is unique and in addition to the spacing thereof, no dot or depression 32 underlies another. That is, when the readout unit R is viewed head-on the depressions of the eleven various characters are so placed that no depression 32 lies beneath another. There may, of course, be exceptions. An example of this feature is illustrated in FIG. 9 wherein the numeral 9 is superimposed over the numeral 0. It will be readily apparent that it is feasible, therefore, to superimpose the characters without overshadowing any of the multiplicity of dotlike depressions 32.

The readout stack S is completed by arranging eleven, for example, character frames F together and by sliding them as a unit into the housing H to a position where the windows 28 align with the window W. In practice, a twelfth plate 33 is employed as a cover to protect the foremost frame F, the plate 33 being polarized so as to filter the light and thereby reduce glare and incident reflections. It is preferred that the polarization be on vertical axes. Further, a thirteenth plate 34 is employed as a back-plate to occupy the remaining space and to present a dull black light absorption finish behind the rearmost frame F.

The blocks L are provided to locate the readout stack S within the housing H and to receive the lamp boards LB with the lamps thereof aligned with the respective apertures 31, as may be required. As is best illustrated in FIG. 5 of the drawings, the blocks L are alike and each substantially occupies an end of the housing interior, leaving a chamber 35 for the reception of the lamp board LB. The block L is a rectangular solid with passages 36 disposed therethrough to open at the inner and outer ends 37 and 38 thereof. As is clearly shown there is a passage 36 aligned with each aperture 31, and since there are two ranks of apertures shown there are two rows of passages each disposed transversely of the block L. With the arrangement of frames F as shown and as above specified, there are four uninterrupted mask rails intermediate opposed apertures 31, with the result that ample space is allowed for passages 36 of substantial diameter. In practice, the passages 36 are made .238 in. in diameter and each is positioned in substantially direct alignment with an aperture31. As a result, light beamed through any one passage 36 will not penetrate to another, the inner end 37 of each block being in direct snug engagement with the rails of the masks 25.

The lamp boards LB are provided to furnish the individual light beams that are projected through the passages 36, there being a lamp board LB at both the top and bottom ends of the structure. The two lamp boards LB are alike and each involves a circuit board 40 which occupies the chamber 35 and a plurality of lamps 45 which occupy the plurality of passages 36. The circuit board 40 is a at element of dielectric material with circuitry 41 imprinted thereon for completing a circuit to each lamp 45 at circuit connections 42, there being a single common connection 43 in the preferred form. As shown, the circuit board 40 occupies the cross-section of the housing H and has a margin or tongue 44 that extends from the back 12 in order to carry a row or series of connectors 46 in the circuits to the lamps 45. The connectors 46 are frictionally received in the receptacle `or receptacles 20 for conducting appropriate electrical currents.

The lamps 45 are arranged on the circuit board 40 in the same pattern as the arrangement of the passages 36, andin practice, cylindrical lamps are employed and which are disposed on axes normal to the plane of the Said board. The electrical connections of the lamps are secured to the printed circuit at terminals, in the usual manner as by soldering or the like. As a result, a bank of lamps 45 is installed in each lamp block L, each lamp being exposed to an aperture 31 and with the connectors 46 exposed and/or contacted to circuitry at the receptacles 20.

The components hereinabove described, including the readout stack S, lamp blocks L and lamp board LB, are positioned within the housing H as specified and preferably secured in said positions as follows:

The readout stack S is free within the housing H and is snugly captured in working position by the spaced lamp blocks L that are secured by fasteners 50 projected through the housing walls. Thus, the lamp boards LB are insertable into the chambers 35 with the lamps 45 projected into their respective passages 36 and with the connectors 46 exposed at the rearwardly projecting tongues 44. As shown, the back 12 of the housing H is recessed at `51 so as to freely pass the projecting tongues. Further, and in order to capture the lamp boards LB and to protectively enclose the same, the opposite ends of the housing H are closed by covers 52. The covers 52 are alike and are secured to the ends 13 of the housing H as by means of fasteners 53 threaded int-o the lamp blocks L. Each of said covers 52 serves dual purposes, firstly for completing the enclosure and secondly for positioning the entire readout unit R. As shown the cover S2 is provided with a rearwardly opening slot 54 adapted to slideable engage over the key 19 that projects from the guide strip 16 or 17 as the case may be, all to the end that the unit R is accurately located and/ or positioned as the connectors 46 are engaged in the receptacles 20 of the mounting circuit board B.

From the foregoing, it will be clear that an extremely compact readout unit is provided Iwherein the readout stack S is reduced to minimum thickness or depth. In actual practice, and with the parts dimensioned as specified the stack of eleven super-imposed character frames F complete with the masks 25 is of .385 in. thickness or depth and with the result that maximum depth displacement between any two characters cannot exceed .350 in. (the thickness or depth from the rear face of the foremost plate 20 to the rear face of the rearmost plate 20'). Therefore, by employing characters or symbols of substantial height, say for example .750 in., and of comparable width the permissible angle of perspective for viewing the characters or symbols is substantial. That is, a person can 0bserve the window W at a substantial angle (in actual practice at an angle up to or about 45) and thereat view any character or symbol in its entirety.

Further, because of the permissible angle of view inherent in the instant readout device or unit R the provision of the mask 25 with marginal portions surrounding the entire Windows 28 is of unique importance. The dull light absorption finish at side 26 faces forwardly and prevents glare to the person viewing the characters, while the specular finish at side 27 increases the efficiency of light directed to the characters. The blocks L are of substantial body and thereby afford heat-sinks for conducting heat from the lamps 45. Also, the passages 36 are provided with specular finished walls and the lamps 45 per se have lens-like tops which focus beams of light along the axes of said passages. Thus, the beams of light are concentrated so as to enter the apertures 31 and the Lucite plates 20 conduct said light to the depressions 32 which are visibly illuminated thereby. The end result is a brilliant specular illumination of the multiplicity of dots which comprise the characters or symbols which are then readily observed.

Having described only a typical preferred form and application of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any modifications or variations that may appear to those skilled in Ithe art and fall within the scope of the following claims.

I claim:

1. A readout unit for discriminate illumination of characters, and including:

(a) a vertical enclosure housing, open therethrough and with a window through one wall thereof;

(b) a stack of character frames slidably received and enclosed in the housing and positioned at said window and each comprising, a plate of light transmitting materialfsupported in a mask coextensive therewith, there being an aperture in one end of each mask to admit light to the plate therein;

(c) spaced upper and lower blocks secured in the housing above and below the ends of said stack, engaged therewith to position the same, and having passages extending therethrough and each passage aligned with an aperture in a mask;

(d) and means above and below said blocks and comprising lamps projecting light through said passages to illuminate said plates individually,

2. A readout unit for discriminate illumination of characters, and including:

(a) a vertical enclosure housing, open therethrough and with a window through one wall thereof;

(b) a stock of character 4frames slidably received and enclosed in the housing and positioned at said window and each comprising, a plate of light transmitting material supported in a mask coextensive therewith, there being an aperture in one end of each mask to admit light to the plate therein;

(d) and a lamp board above and below said blocks ing above and below the ends of said stack, engaged therewith to position the same, and having passages extending therethrough and each passage aligned with an aperture in a mask; respectively and each comprising a circuit board with lamps projecting therefrom and into said passages, individually, and operable when lighted to direct beams of light through said passages and aligned apertures to illuminate said plates individually.

3. A readout unit for discriminate illumination of characters, and including:

(a) a vertically enclosure housing, open therethrough and with a window at the front thereof;

(b) a stack of character frames carried and enclosed in the housing at said window and each comprising, a plate of light transmitting material supported in a mask coextensive therewith, there being an aperture in each mask to admit light to the plate therein;

(c) and means externally of the stack of character frames to discriminately beam light through each aperture to illuminate each plate individually.

4. A readout unit for discriminate illumination of characters, and including:

(a) a vertically enclosure housing, open therethrough and with a window at the front thereof;

(b) a stack of character frames carried and enclosed in the housing at said window and each comprising, a plate of light transmitting material, and a mask coextensive with and supporting the plate and having dull finished forwardly disposed surfaces and having specular finished rearwardly disposed surfaces, there being an aperture in each mask to admit light to the plate therein;

(c) and means externally of the stack of character frames to discriminately beam light through each aperture to illuminate each plate individually.

5. A readout unit for discriminate illumination of characters, and including:

(a) a Vertical enclosure housing, open therethrough and with a window at the front thereof;

(b) a stack of character frames carried and enclosed in the housing at said window and each comprising, a plate of light transmitting material, and a mask coexte-nsive with the `plate and having a rail slideably receiving and supporting the plate therein, there being an aperture in the rail of each mask to admit light to the plate therein;

(c) and means externally of the stack of character `frames to discriminately beam light through each aperture to illuminate each plate individually. p

6. A readout unit for discriminate illumination of characters, and including:

(a) a vertically enclosure housing, open therethrough and with a Window at the front thereof;

(b) a stack of character frames carried and enclosed in the housing at said Window and each comprising, a plate of light transmitting material, and a mask coextensive with the plate and having a rail slideably receiving and supporting the plate therein, there being an aperture in each mask rail and said apertures being in staggered positions relative to each other;

(c) and means externally of the stack of character frames and comprising a multiplicity of lamps, each lamp being positionedto discriminately beam light f to an individual aperture to illuminate each plate individually.

7. A readout unit for discriminate illumination of characters, and including:

(a) a vertical enclosure housing, open therethrough and with a window at the front thereof;

(b) a stack of character frames carried and enclosed in the housing at said window and each comprising, a plate of light transmitting material, and a mask eoextensive with and supporting the plate therein, said mask having an aperture at one end and sequential masks being arranged oppositely end for end;

(c) and means externally of the stack of character frames at opposite ends of the housing to discriminately beam light through each aperture to illuminate each plate individually.

8. A readout unit for discriminate illumination of characters, and including:

(a) a vertical enclosure housing, open therethrough and with a window at the front thereof;

(b) a stack of character frames carried and enclosed in the housing at said Window and each comprising a plate of light transmitting material, and a mask coextensive with and supporting the plate therein, said mask having an aperture at one end sequential masks being arranged oppositely end for end, and said apertures at one end being in staggered positions relative to each other;

(c) and means externally of and at opposite ends' of the stack of character frames and comprising a multiplicity of lamps, each lamp being positioned to discriminately beam light to an individual aperture to illuminate each plate individually.

References Cited UNITED STATES PATENTS JOHN W. CALDWELL, Primary Examiner.

NEIL C. READ, Examiner.

I. J. LEVIN, H. I. PITTS, Assistant Examiners. 

